Hilton John Van Staden, a 52-year-old South African, pleaded guilty on Friday at Bristol Crown Court to conspiracy to import drugs.

Fifteen people have been convicted worldwide and customs officers say they have disrupted a major global trafficking ring.

Sentences totalling 206 years have already been handed out following a massive customs operation involving South America, Europe and the Caribbean.

John Van Staden was sentenced to nine years

Judge John Foley told Staden he would not be considered for parole until he had served half of his sentence, and would probably not be released until he had served at least two-thirds.

The judge said: "Those who are part of conspiracies to smuggle large quantities of class A drugs, if they are successful, achieve substantial rewards.

"If they are unsuccessful they achieve substantial penalties and your case is no exception."

In 1996 an Irish vessel called the Sea Mist, destined for the UK, was searched by customs officials in Cork.

Officials found nearly 600 kilos of cocaine, triggering an international intelligence operation.

Over a six-year period 15 people were arrested and convicted in the UK and abroad.

The court heard how Staden, a keen sailor with good contacts in the yachting industry, became involved in the drugs smuggling ring in 1997 when approached by his friend and gang member Godfried Hoppenbrouwers.

This was a complex and lengthy case that took our officers across the world

Jim Fitzpatrick, investigation officer

The court heard Staden organised yachts to transport millions of pounds worth of cocaine from the Caribbean to the UK, but had little direct contact with the drugs.

Mark Sutherland-Williams, prosecuting, said that in 1998 Staden brought three or four yachts "loaded with drugs" from the West Indies to the UK.

Staden was arrested in London in March 2000 when he tried to access a safety deposit box, in which he kept about £500,000 in cash and contact details for the other members of the drugs smuggling gang.

Craig Rush, defending, said Staden was a "decent man" who had "succumbed to greed".

Mr Rush said Staden was not a major player in the drugs smuggling operation and credit should be given to him for his guilty plea and the fact that he was a foreign prisoner who was away from his wife and family.

After the sentencing, assistant chief investigation officer, Jim Fitzpatrick, said: "This was a complex and lengthy case that took our officers across the world.

"They showed dedication and professionalism throughout the whole investigation and trial."

Despite the convictions, the alleged mastermind behind the massive operation, financier, Brian Brendan Wright, escaped to Cyprus.

Wright, 54, a financier with links to the British horse racing industry, is thought to have fled to Cyprus, which does not have an extradition treaty with Britain.